db/queries/posts.sql

@@ -63,7 +63,7 @@ WHERE id = sqlc.arg(id);
 
 -- name: CreatePostImage :exec
 INSERT INTO post_images (
-  id, post_id, object_key, public_url, description, position, width, height, created_at
+  id, post_id, object_key, public_url, description, kind, position, width, height, created_at
 )
 VALUES (
   sqlc.arg(id),
@@ -71,6 +71,7 @@ VALUES (
   sqlc.arg(object_key),
   sqlc.arg(public_url),
   sqlc.arg(description),
+  sqlc.arg(kind),
   sqlc.arg(position),
   sqlc.arg(width),
   sqlc.arg(height),
@@ -83,7 +84,7 @@ WHERE post_id = sqlc.arg(post_id);
 
 -- name: ListPostImages :many
 SELECT
-  id, post_id, object_key, public_url, description, position, width, height, created_at
+  id, post_id, object_key, public_url, description, kind, position, width, height, created_at
 FROM post_images
 WHERE post_id = sqlc.arg(post_id)
 ORDER BY position;
@@ -102,7 +103,7 @@ WITH RECURSIVE thread AS (
 )
 SELECT
   images.id, images.post_id, images.object_key, images.public_url,
-  images.description, images.position, images.width, images.height, images.created_at
+  images.description, images.kind, images.position, images.width, images.height, images.created_at
 FROM post_images images
 JOIN thread ON thread.id = images.post_id
 ORDER BY images.post_id, images.position;

internal/store/migrate.go

@@ -158,6 +158,32 @@ CREATE UNIQUE INDEX IF NOT EXISTS discord_post_links_thread_uidx
 	return nil
 }
 
+func migratePostImageVideo(ctx context.Context, exec execContext) error {
+	steps := []struct {
+		name string
+		sql  string
+	}{
+		{"add kind", `ALTER TABLE post_images ADD COLUMN IF NOT EXISTS kind TEXT NOT NULL DEFAULT 'image'`},
+		{"drop kind check", `ALTER TABLE post_images DROP CONSTRAINT IF EXISTS post_images_kind_check`},
+		{"add kind check", `ALTER TABLE post_images ADD CONSTRAINT post_images_kind_check CHECK (kind IN ('image', 'video'))`},
+		{"drop width check", `ALTER TABLE post_images DROP CONSTRAINT IF EXISTS post_images_width_check`},
+		{"drop height check", `ALTER TABLE post_images DROP CONSTRAINT IF EXISTS post_images_height_check`},
+		{"add width check", `ALTER TABLE post_images ADD CONSTRAINT post_images_width_check CHECK (width >= 0)`},
+		{"add height check", `ALTER TABLE post_images ADD CONSTRAINT post_images_height_check CHECK (height >= 0)`},
+		{"drop image dims check", `ALTER TABLE post_images DROP CONSTRAINT IF EXISTS post_images_image_dims_check`},
+		{"add image dims check", `ALTER TABLE post_images ADD CONSTRAINT post_images_image_dims_check CHECK (kind <> 'image' OR (width > 0 AND height > 0))`},
+		{"drop position check", `ALTER TABLE post_images DROP CONSTRAINT IF EXISTS post_images_position_check`},
+		{"add position check", `ALTER TABLE post_images ADD CONSTRAINT post_images_position_check CHECK (position BETWEEN 0 AND 4)`},
+		{"one video index", `CREATE UNIQUE INDEX IF NOT EXISTS post_images_one_video_uidx ON post_images (post_id) WHERE kind = 'video'`},
+	}
+	for _, step := range steps {
+		if _, err := exec.ExecContext(ctx, step.sql); err != nil {
+			return fmt.Errorf("%s: %w", step.name, err)
+		}
+	}
+	return nil
+}
+
 func migratePostDate(ctx context.Context, exec execContext) error {
 	steps := []struct {
 		name string
@@ -351,6 +377,7 @@ CREATE TABLE IF NOT EXISTS schema_migrations (
 		{"009_drop_legacy_post_tables", migrateDropLegacyPostTables},
 		{"010_post_images", migratePostImages},
 		{"011_discord_post_links", migrateDiscordPostLinks},
+		{"012_post_image_video", migratePostImageVideo},
 	}
 	for _, m := range migrations {
 		if applied[m.version] {

internal/store/migrate_posts_test.go

@@ -87,6 +87,12 @@ CREATE TABLE users (
 	if err := migrateDiscordPostLinks(ctx, conn); err != nil {
 		t.Fatalf("discord post links migration is not idempotent: %v", err)
 	}
+	if err := migratePostImageVideo(ctx, conn); err != nil {
+		t.Fatal(err)
+	}
+	if err := migratePostImageVideo(ctx, conn); err != nil {
+		t.Fatalf("post image video migration is not idempotent: %v", err)
+	}
 	if _, err := conn.ExecContext(ctx, `
 INSERT INTO users (id, name, role)
 VALUES ('homeowner', 'Home Owner', 'user'), ('plumber', 'The Plumber', 'admin');
@@ -118,9 +124,9 @@ VALUES ('homeowner', 'root-1', 1);`); err != nil {
 	}
 	imageQueries := sqlc.New(conn)
 	for _, image := range []sqlc.CreatePostImageParams{
-		{ID: "root-image-1", PostID: "root-1", ObjectKey: "posts/root-1/1.jpg", PublicUrl: "https://cdn.example/root-1.jpg", Description: "Valve", Position: 0, Width: 1200, Height: 900, CreatedAt: "2026-08-26T08:00:00Z"},
+		{ID: "root-image-1", PostID: "root-1", ObjectKey: "posts/root-1/1.jpg", PublicUrl: "https://cdn.example/root-1.jpg", Description: "Valve", Kind: "image", Position: 0, Width: 1200, Height: 900, CreatedAt: "2026-08-26T08:00:00Z"},
-		{ID: "root-image-2", PostID: "root-1", ObjectKey: "posts/root-1/2.png", PublicUrl: "https://cdn.example/root-2.png", Position: 1, Width: 900, Height: 1200, CreatedAt: "2026-08-26T08:00:00Z"},
+		{ID: "root-image-2", PostID: "root-1", ObjectKey: "posts/root-1/2.png", PublicUrl: "https://cdn.example/root-2.png", Kind: "image", Position: 1, Width: 900, Height: 1200, CreatedAt: "2026-08-26T08:00:00Z"},
-		{ID: "reply-image-1", PostID: "reply-1", ObjectKey: "posts/reply-1/1.jpg", PublicUrl: "https://cdn.example/reply-1.jpg", Description: "Cartridge", Position: 0, Width: 1000, Height: 1000, CreatedAt: "2026-08-26T09:00:00Z"},
+		{ID: "reply-image-1", PostID: "reply-1", ObjectKey: "posts/reply-1/1.jpg", PublicUrl: "https://cdn.example/reply-1.jpg", Description: "Cartridge", Kind: "image", Position: 0, Width: 1000, Height: 1000, CreatedAt: "2026-08-26T09:00:00Z"},
 	} {
 		if err := imageQueries.CreatePostImage(ctx, image); err != nil {
 			t.Fatal(err)
@@ -144,10 +150,24 @@ VALUES ('homeowner', 'root-1', 1);`); err != nil {
 	}
 	if err := imageQueries.CreatePostImage(ctx, sqlc.CreatePostImageParams{
 		ID: "too-many", PostID: "root-1", ObjectKey: "posts/root-1/5.jpg",
-		PublicUrl: "https://cdn.example/root-5.jpg", Position: 4,
+		PublicUrl: "https://cdn.example/root-5.jpg", Kind: "image", Position: 5,
 		Width: 100, Height: 100, CreatedAt: "2026-08-26T08:00:00Z",
 	}); err == nil {
-		t.Fatal("fifth image position unexpectedly succeeded")
+		t.Fatal("position 5 unexpectedly succeeded")
+	}
+	if err := imageQueries.CreatePostImage(ctx, sqlc.CreatePostImageParams{
+		ID: "root-video-1", PostID: "root-1", ObjectKey: "posts/root-1/clip.mp4",
+		PublicUrl: "https://cdn.example/clip.mp4", Kind: "video", Position: 2,
+		Width: 0, Height: 0, CreatedAt: "2026-08-26T08:00:00Z",
+	}); err != nil {
+		t.Fatal(err)
+	}
+	if err := imageQueries.CreatePostImage(ctx, sqlc.CreatePostImageParams{
+		ID: "root-video-2", PostID: "root-1", ObjectKey: "posts/root-1/clip-2.mp4",
+		PublicUrl: "https://cdn.example/clip-2.mp4", Kind: "video", Position: 3,
+		Width: 0, Height: 0, CreatedAt: "2026-08-26T08:00:00Z",
+	}); err == nil {
+		t.Fatal("second video unexpectedly succeeded")
 	}
 	if err := imageQueries.UpsertDiscordPostLink(ctx, sqlc.UpsertDiscordPostLinkParams{
 		PostID:           "root-1",

internal/store/post.go

@@ -29,16 +29,20 @@ const (
 	PostStateHidden          PostState = "hidden"
 	PostStateLocked          PostState = "locked"
 	MaxPostImages                      = 4
+	MaxPostVideos                      = 1
 	MaxImageDescriptionRunes           = 500
+	MediaKindImage                     = "image"
+	MediaKindVideo                     = "video"
 )
 
-// PostImage is one ordered public image attached to a post.
+// PostImage is one ordered public image or video attached to a post.
 type PostImage struct {
 	ID          string
 	PostID      string
 	ObjectKey   string
 	PublicURL   string
 	Description string
+	Kind        string
 	Position    int
 	Width       int
 	Height      int
@@ -200,12 +204,13 @@ func preparePost(p *Post) error {
 }
 
 func preparePostImages(p *Post) error {
-	if len(p.Images) > MaxPostImages {
+	if len(p.Images) > MaxPostImages+MaxPostVideos {
-		return fmt.Errorf("%w: at most %d images are allowed", ErrInvalidPost, MaxPostImages)
+		return fmt.Errorf("%w: at most %d images and %d video are allowed", ErrInvalidPost, MaxPostImages, MaxPostVideos)
 	}
 	ids := make(map[string]bool, len(p.Images))
 	keys := make(map[string]bool, len(p.Images))
 	now := time.Now().UTC().Format(time.RFC3339Nano)
+	images, videos := 0, 0
 	for i := range p.Images {
 		image := &p.Images[i]
 		image.ID = strings.TrimSpace(image.ID)
@@ -213,6 +218,13 @@ func preparePostImages(p *Post) error {
 		image.ObjectKey = strings.TrimSpace(image.ObjectKey)
 		image.PublicURL = strings.TrimSpace(image.PublicURL)
 		image.Description = strings.TrimSpace(image.Description)
+		image.Kind = strings.TrimSpace(image.Kind)
+		if image.Kind == "" {
+			image.Kind = MediaKindImage
+		}
+		if image.Kind != MediaKindImage && image.Kind != MediaKindVideo {
+			return fmt.Errorf("%w: invalid media kind", ErrInvalidPost)
+		}
 		if image.ID == "" {
 			image.ID = uuid.NewString()
 		}
@@ -228,10 +240,19 @@ func preparePostImages(p *Post) error {
 		if len([]rune(image.Description)) > MaxImageDescriptionRunes {
 			return fmt.Errorf("%w: image description is too long", ErrInvalidPost)
 		}
+		if image.Kind == MediaKindImage {
+			images++
 			if image.Width <= 0 || image.Height <= 0 ||
 				image.Width > math.MaxInt32 || image.Height > math.MaxInt32 {
 				return fmt.Errorf("%w: invalid image dimensions", ErrInvalidPost)
 			}
+		} else {
+			videos++
+			if image.Width < 0 || image.Height < 0 ||
+				image.Width > math.MaxInt32 || image.Height > math.MaxInt32 {
+				return fmt.Errorf("%w: invalid video dimensions", ErrInvalidPost)
+			}
+		}
 		if ids[image.ID] || keys[image.ObjectKey] {
 			return fmt.Errorf("%w: duplicate image", ErrInvalidPost)
 		}
@@ -242,6 +263,12 @@ func preparePostImages(p *Post) error {
 			image.CreatedAt = now
 		}
 	}
+	if images > MaxPostImages {
+		return fmt.Errorf("%w: at most %d images are allowed", ErrInvalidPost, MaxPostImages)
+	}
+	if videos > MaxPostVideos {
+		return fmt.Errorf("%w: at most %d video is allowed", ErrInvalidPost, MaxPostVideos)
+	}
 	return nil
 }
 
@@ -253,6 +280,7 @@ func createPostImages(ctx context.Context, q *sqlc.Queries, images []PostImage)
 			ObjectKey:   image.ObjectKey,
 			PublicUrl:   image.PublicURL,
 			Description: image.Description,
+			Kind:        image.Kind,
 			Position:    int16(image.Position),
 			Width:       int32(image.Width),
 			Height:      int32(image.Height),
@@ -271,6 +299,7 @@ func postImageFromSQL(image sqlc.PostImage) PostImage {
 		ObjectKey:   image.ObjectKey,
 		PublicURL:   image.PublicUrl,
 		Description: image.Description,
+		Kind:        image.Kind,
 		Position:    int(image.Position),
 		Width:       int(image.Width),
 		Height:      int(image.Height),

internal/store/post_test.go

@@ -338,6 +338,36 @@ func TestMemoryPostImages(t *testing.T) {
 	if err := mem.CreatePost(ctx, tooMany); !errors.Is(err, ErrInvalidPost) {
 		t.Fatalf("five-image create error = %v, want ErrInvalidPost", err)
 	}
+
+	withVideo := &Post{
+		AuthorID: homeowner.ID,
+		Title:    "With video",
+		Body:     "Four photos and a clip.",
+		Images: append(validPostImages(4), PostImage{
+			ID:        "clip-1",
+			ObjectKey: "posts/clip-1.mp4",
+			PublicURL: "https://cdn.example/clip-1.mp4",
+			Kind:      MediaKindVideo,
+		}),
+	}
+	if err := mem.CreatePost(ctx, withVideo); err != nil {
+		t.Fatalf("four images and one video: %v", err)
+	}
+	if withVideo.Images[4].Kind != MediaKindVideo || withVideo.Images[4].Position != 4 {
+		t.Fatalf("video not stored: %+v", withVideo.Images[4])
+	}
+	twoVideos := &Post{
+		AuthorID: homeowner.ID,
+		Title:    "Two clips",
+		Body:     "Not allowed.",
+		Images: []PostImage{
+			{ObjectKey: "posts/a.mp4", PublicURL: "https://cdn.example/a.mp4", Kind: MediaKindVideo},
+			{ObjectKey: "posts/b.mp4", PublicURL: "https://cdn.example/b.mp4", Kind: MediaKindVideo},
+		},
+	}
+	if err := mem.CreatePost(ctx, twoVideos); !errors.Is(err, ErrInvalidPost) {
+		t.Fatalf("two-video create error = %v, want ErrInvalidPost", err)
+	}
 }
 
 func validPostImages(count int) []PostImage {

internal/store/sqlc/models.go

@@ -35,6 +35,7 @@ type PostImage struct {
 	ObjectKey   string
 	PublicUrl   string
 	Description string
+	Kind        string
 	Position    int16
 	Width       int32
 	Height      int32

internal/store/sqlc/posts.sql.go

@@ -59,7 +59,7 @@ func (q *Queries) CreatePost(ctx context.Context, arg CreatePostParams) error {
 
 const createPostImage = `-- name: CreatePostImage :exec
 INSERT INTO post_images (
-  id, post_id, object_key, public_url, description, position, width, height, created_at
+  id, post_id, object_key, public_url, description, kind, position, width, height, created_at
 )
 VALUES (
   $1,
@@ -70,7 +70,8 @@ VALUES (
   $6,
   $7,
   $8,
-  $9
+  $9,
+  $10
 )
 `
 
@@ -80,6 +81,7 @@ type CreatePostImageParams struct {
 	ObjectKey   string
 	PublicUrl   string
 	Description string
+	Kind        string
 	Position    int16
 	Width       int32
 	Height      int32
@@ -93,6 +95,7 @@ func (q *Queries) CreatePostImage(ctx context.Context, arg CreatePostImageParams
 		arg.ObjectKey,
 		arg.PublicUrl,
 		arg.Description,
+		arg.Kind,
 		arg.Position,
 		arg.Width,
 		arg.Height,
@@ -201,7 +204,7 @@ func (q *Queries) GetRootPostVoteSummary(ctx context.Context, arg GetRootPostVot
 
 const listPostImages = `-- name: ListPostImages :many
 SELECT
-  id, post_id, object_key, public_url, description, position, width, height, created_at
+  id, post_id, object_key, public_url, description, kind, position, width, height, created_at
 FROM post_images
 WHERE post_id = $1
 ORDER BY position
@@ -222,6 +225,7 @@ func (q *Queries) ListPostImages(ctx context.Context, postID string) ([]PostImag
 			&i.ObjectKey,
 			&i.PublicUrl,
 			&i.Description,
+			&i.Kind,
 			&i.Position,
 			&i.Width,
 			&i.Height,
@@ -327,7 +331,7 @@ WITH RECURSIVE thread AS (
 )
 SELECT
   images.id, images.post_id, images.object_key, images.public_url,
-  images.description, images.position, images.width, images.height, images.created_at
+  images.description, images.kind, images.position, images.width, images.height, images.created_at
 FROM post_images images
 JOIN thread ON thread.id = images.post_id
 ORDER BY images.post_id, images.position
@@ -348,6 +352,7 @@ func (q *Queries) ListPostThreadImages(ctx context.Context, rootID string) ([]Po
 			&i.ObjectKey,
 			&i.PublicUrl,
 			&i.Description,
+			&i.Kind,
 			&i.Position,
 			&i.Width,
 			&i.Height,

schema.sql

@@ -48,13 +48,23 @@ CREATE TABLE IF NOT EXISTS post_images (
   object_key TEXT NOT NULL UNIQUE,
   public_url TEXT NOT NULL,
   description TEXT NOT NULL DEFAULT '' CHECK (char_length(description) <= 500),
-  position SMALLINT NOT NULL CHECK (position BETWEEN 0 AND 3),
+  kind TEXT NOT NULL DEFAULT 'image',
-  width INTEGER NOT NULL CHECK (width > 0),
+  position SMALLINT NOT NULL,
-  height INTEGER NOT NULL CHECK (height > 0),
+  width INTEGER NOT NULL,
+  height INTEGER NOT NULL,
   created_at TEXT NOT NULL,
+  CONSTRAINT post_images_kind_check CHECK (kind IN ('image', 'video')),
+  CONSTRAINT post_images_width_check CHECK (width >= 0),
+  CONSTRAINT post_images_height_check CHECK (height >= 0),
+  CONSTRAINT post_images_image_dims_check CHECK (kind <> 'image' OR (width > 0 AND height > 0)),
+  CONSTRAINT post_images_position_check CHECK (position BETWEEN 0 AND 4),
   UNIQUE (post_id, position)
 );
 
+CREATE UNIQUE INDEX IF NOT EXISTS post_images_one_video_uidx
+  ON post_images (post_id)
+  WHERE kind = 'video';
+
 CREATE TABLE IF NOT EXISTS post_votes (
   user_id TEXT NOT NULL REFERENCES users(id),
   post_id TEXT NOT NULL REFERENCES posts(id) ON DELETE CASCADE,